A noise filter that is capable of efficiently removing noise even in a case where a ferrite core having two divided core portions is used. The noise filter includes a tubular ferrite core. The ferrite core includes two divided core portions. The two divided core portions are configured to be divided along divided end surfaces in an axial direction of the ferrite core. The two divided core portions include a platinum group metal in an amount of 0.5% to 2.0% with respect to the total weight of a ferrite powder.

The present invention provides a magnetic multilayer pigment flake and a magnetic coating composition that are relatively safe for human health and the environment. The pigment flake includes one or more magnetic layers of a magnetic alloy and one or more dielectric layers of a dielectric material. The magnetic alloy is an iron-chromium alloy or an iron-chromium-aluminum alloy, having a substantially nickel-free composition. The coating composition includes a plurality of the pigment flakes disposed in a binder medium.

This ferrite magnet has a ferrite phase having a magnetoplumbite structure, and an orthoferrite phase, and is characterized in that the composition ratios of the total of each metal element A, R, Fe and Me is represented by expression (1) A.sub.1-xR.sub.x(Fe.sub.12-yMe.sub.y).sub.z, (in expression (1), A is at least one element selected from Sr, Ba, Ca and Pb; R is at least one element selected from the rare-earth elements (including Y) and Bi, and includes at least La, and Me is Co, or Co and Zn) and in that the content (m) of the orthoferrite phase is 0<m<28.0 in mol %. The invention makes it possible to achieve a ferrite magnet with increased Br.

An exemplary embodiment of the present invention provides a stylus pen including: a body; a conductive tip configured to be exposed from an inside of the body to an outside thereof; and a resonance circuit connected to the conductive tip to resonate an electrical signal transferred from the conductive tip. An inductor unit of the resonance circuit includes a ferrite core and a coil wound in multiple layers over at least a portion of the ferrite core. The ferrite core includes nickel, and the coil can be formed by a litz wire with adjacent winding layers that are wound to be inclined in a zigzag form.

The present invention provides a ferrite sintered magnet comprising (1) main phase grains containing a ferrite having a hexagonal structure, (2) two-grain boundaries formed between two of the main phase grains, and (3) multi-grain boundaries surrounded by three or more of the main phase grains. The above ferrite sintered magnet comprises Ca, R, Sr, Fe and Co, with R being at least one element selected from the group consisting of rare earth elements and Bi, and comprising at least La. The number Nm of the above main phase grains and the number Ng of the above multi-grain boundaries in the cross section including the direction of the easy magnetization axis of the above ferrite sintered magnet satisfy the formula (1A):
50%≤Nm/(Nm+Ng)≤65%  (1A).

A sintered ferrite magnet having a composition of metal elements of Ca, R, A, Fe and Co, which is represented by the general formula of Ca.sub.1-x-yR.sub.xA.sub.yFe.sub.2n-zCo.sub.z, wherein R is at least one of rare earth elements indispensably including La; A is Sr and/or Ba; x, y, z and n represent the atomic ratios of Ca, R, A, Fe and Co; 2n represents a molar ratio expressed by 2n=(Fe+Co)/(Ca+R+A); and x, y, z and n meet the conditions of 0.15≤x≤0.35, 0.05≤y≤0.40, (1-x-y)>y, 0<z≤0.18, and 7.5≤(2n-z)<11.0.

A magnetic device and method for providing the magnetic device are disclosed. The magnetic device includes a multilayer structure and a magnetic layer. The multilayer structure includes alternating layers of A and E. A includes a first material. The first material includes at least one of Co, Ru, or Ir. The first material may include an IrCo alloy. E includes at least one other material that includes Al. The other material(s) may include an alloy selected from AlGa, AlSn, AlGe, AlGaGe, AlGaSn, AlGeSn, and AlGaGeSn. A composition of the multilayer structure is represented by A.sub.1-xE.sub.x, where x is at least 0.45 and not more than 0.55. The magnetic layer includes an Al-doped Heusler compound. The magnetic layer shares an interface with the multilayer structure.

Active-mode sensors are provided, and may be used to detect air, water, and sediment interfaces. Systems and methods for sensing air, water, and sediment are also provided. The sensors are robust and withstand forces due to moving or shifting water and sediment.

An exemplary embodiment of the present invention provides a stylus pen including: a body; a conductive tip configured to be exposed from an inside of the body to an outside thereof; and a resonance circuit connected to the conductive tip to resonate an electrical signal transferred from the conductive tip. An inductor unit of the resonance circuit includes a ferrite core and a coil wound in multiple layers over at least a portion of the ferrite core. The ferrite core includes nickel, and the coil can be formed by a litz wire with adjacent winding layers that are wound to be inclined in a zigzag form.

The rotor of a rotor assembly for an electric machine includes first magnetic structures utilized for torque production in the electric machine. Second magnetic structures including second magnetic poles not utilized for torque production in the electric machine are polymer-bonded to at least one of the rotor and the rotor shaft.